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sqlsql-serverdifference

How can I "subtract" one table from another?

I have a master table A, with ~9 million rows. Another table B (same structure) has ~28K rows from table A. What would be the best way to remove all contents of B from table A?

The combination of all columns (~10) are unique. Nothing more in the form a of a unique key.

Solution

  • If you have sufficient rights you can create a new table and rename that one to A. To create the new table you can use the following script:

    CREATE TABLE TEMP_A AS
SELECT *
FROM   A
MINUS
SELECT *
FROM   B

    This should perform pretty good.